Shoe bottom construction and method of making shoes and shoes bottom units



Sept. 29, 1936. K. KxLBURN 2,055,542

SHOE BOTTOM CONSTRUCTION AND METHOD OY' MAKING SHOES AND SHOE BOTTOM UNITS Filed Nov. 25, 1951 2 Sheets-Sheet l www,

Sept. 29, 1936. l Kl KILBURN v 2,055,542

SHOE BOTTOM CONSTRUCTION AND METHOD OF MAKING SHOES AND SHOE BOTTOM UNITS Filed Nov. 25, 1931 2 Sheets-Sheet 2 MMM Patented Sept. 29, 1936 iTED STATE PATENT OFFICE SHOE BOTTOM CONSTRUCTION AND METH- OD OF MAKING SHOES AND SHOE BOT- TOM UNITS Application November 25, 1931i, Serial No., 577,297

l2 (Clas.

This invention relates to improvements in shoe bottom units and methods of making the same and to improvements in shoes and methods of shoemaking.

ln the manufacture of McKay-served shoes in which the outsoles are laid with cement as Well as in the manufacture of so-called cement process shoes in which cement is the only or principal means employed for securing the outsoles to the shoesit is often diicult, particularly .in the case of shoes with narrow Shanks, to secure satisfactory adhesion between the outsole and the bottom of the lasted shoe inthe narrow shank portion of the shoe. Dimculty is also commonly experienced in conforming the shank portion of the outsole and adjacent portions of the upper to the contour oi the corresponding surfaces of the last so that the lines oi the last vll be accurately reproduced in the finished s oe.

One object of the present invention is to provide improvements in shoe bottom construction such, for example, as improvements in the construction of reinforced. insoles, the use of which will aid overcoming the above-mentioned diniculties.

With this object in view the invention provides a shoe bottom unit of novel construction comprising a shoe bottom member, for example, a full length, insole, and a reinforcing member or filler piece which, as herein illustrated, is mpreg hated with a stiiening or hardening medium and overlies the heel and shank portions of the insole throughout the full v/iclth of said portions, the shoe bottom member having a longitudinally and transversely molded shank portion and the reiniorcing member being longitudinally and transversely molded to conform to the molded shank portion oi the bottom member, and said members being secured together adhesively by the stidening or hardening medium. The illustrated reinforcing member is made or berboard or like material impregnated with an ingredient such as shellac which stifiens or toughens the berboard so that it will function to preserve the molded contour of the insole throughout the life of the shoe but which nevertheless renders the reini'orcing member capable of being readily softened to facilitate the molding of the unit. The shoe bottom or insole unit shown herein comprises also a resilient metallic shank stidener which is curved lengthwise to correspond to the molded longitudinal curvature of the insole and the ller piece, and nearly all ci which at least is interposed betvveen the insole and reinforcing member.

(Cl. i12-146) With this arrangement there is no substantial portion of the metallic stiffener projecting above the overlasted upper margins to engage the outsole and to reduce the Width of shoe bottom area available for adhesive attachment of the outsole in the shank portion of the shoe. This greatly facilitates the securing of suitable adhesion between-the outsole and theshoe bottom in the shank portion of the shoe and consequently is particularly advantageous in cases Where the shank portion of the shoe is particularly narrow. The molded shank portions of the insole and reinforcing member conform closely to the last bottom thereby facilitating tight lasting of the upper and aliording a solid backing for the fastener-driving devices of the lasting machine. lllhis enables the fastenings for the overlasted upper margins to be driven uniformly and in a manner to secure effective holding engagement with the insole unit so as to maintain vthe tension of the upper throughout subsequent shoemaking operations and thus to insure that the upper will conform closely to the lines of the last in the shank portion of the shoe. Moreover, the molded reinforcing member or iller piece provides, in the shank portion of the shoe bottom, an outsole-engaging surface which is smooth and even and of the same contour as the corresponding surface of the last bottom,7 thereby insuring that the lines of the last bottom will be reproduced in the outsole. Further to insure that the shoe upper shall not be held away from the last by the edges of the insole in the shank of the shoe but shall be drawn smoothly over the insole edges without any abrupt -departure from the prole curvatures of the opnl posite sides of the last in that locality, the edges of the insole unit, as herein shown, are beveled at such an angle as to blend with the prole of the last.

Considered in another aspect the invention provides an improved method of sho'emaking in accordance with which, as herein exemplied, an

insole is placed upon a last the bottom of which is longitudinally concave and transversely convex in its shank portion, a shank stiffener, curved to correspond to the longitudinal curvature of the shank portion of the last bottom, is positioned upon the insole, a relatively stii reinforcing member having a sticky surface is placed upon the heel and shank portion of the insole so as substantially to cover the shank stiflener, and molding pressure is applied to the shank portions oi' the insole and the reinforcing member to mold them to fit the last bottom and to secure them adhesively to aotasee together, thereby producing a reinforced shoe bottom or insole unit the advantages of which have already been referred to. The illustrated reinforcing member or ller piece, which, as above mentioned, is made of berboard impregnated with shellac, is prepared or conditioned for the molding operation by the application thereto of a solvent, such as alcohol, which both softens the material and renders it sticky so that the application of pressure to the assembled elements upon the last or form will result in molding the insole and the reinforcing member to the contour of the last and also in adhesively securing the insole and the reinforcing member together. As exemplified herein, the insole unit is molded upon a last over which the shoe upper is subsequently to be lasted and after the unit has been molded and while it is on the last the margins of the unit are beveled along the shank and heel portions so as to blend with the prole of the last.

The invention further consists in improvements in methods of shoe making hereinafter described and claimed, the advantages of which will be apparent to those skilled in the art from the following description.

IThe invention will be explained with reference to the accompanying drawings, in which Fig. l is a perspective View of an insole illustrating the manner in which the insole is treated preparatory tothe assembly `of a reinforcing member therewith;

Fig. 2 is a perspective view of apparatus adapted to be used in connection with the preparation of the reinforcing members for assembly with the insole;

Fig. 3 is a perspective View of a last having an insole and a shank stiffener positioned thereon;

Fig. i is a longitudinal sectional view of a shoe form which may be employed instead of the last shown in Fig. 3;

Fig. 5 is a view similar to Fig. 3 but showing a reinforcing member assembled with the shank stiifener and insole on the last bottom;

Fig. 6 is a fragmentary view, partially in elevation and partially in section, of a portion of a sole pressing machine illustrating the manner in which the reinforced insole is molded;

Fig. 7 is a sectional view taken on the line VII-VII of Fig. 6;

Fig. 8 is a View, partially in section and partially in elevation, illustrating the step of beveling the margin of the reinforced insole;

Fig. 9 is a perspective view of the reinforced insole as it appears when completed; and

Fig. l0 is a sectional View, on an enlarged scale, of a finished shoe in which the insole shown in Fig. 9 has been incorporated.

As shown in Fig. 9 of the drawings, the improved insole or shoe bottom unit ifi comprises an insole l5, a reinforcing member or filler piece for the heel and shank portions of the insole, and

a shank stiifener 29. The marginal contour of the reinforcing member it corresponds to that of the heel and shank'portions of the insole and the reinforcing member is adhesively secured to the insole so that it extends throughout the full length and width of the shank and heel portions of the latter, the rear and lateral edges of the reinforcing member coinciding with the corresponding edges of the insole.Y The shank stiffener 29 consists of a narrow strip of resilient metal curved longitudinally to correspond to the longitudinal curvature of the shank portion of the bottom of a last for a shoe in which the insole is to be incorporated. above-mentioned parts by adhesive of the outsole to the shoe.

are assembled with the shank stiffener if@ interposed between the insole and the reinforcing member i9 and the insole and the reinforcing member are molded to conform to the contour of the last bottom. The reinforcing member it is herein shown as being applied to the outer side of the insole although it may be desirable in certain instances to apply the reinforcing member to the inner side of the insole. In either case, however, the shank stiffener 2i) will be interposed between the reinforcing member and the insole where'it will be protected against accidental displacement and prevented from engaging the outsole and interfering with the secure attachment The edges of the reinforcing member and the corresponding edges of the insole are beveled, as shown at 22 in Fig. 9, so that the profile of the shank and heel portions of the shoe bottom unit will merge smoothly into the prole of the last employed in making the shoe in which the insole is to be incorporated. To facilitate the molding of the insole unit the reinforcing member i8 is made of material which is capable of being readily softened before being subjected to the molding operation and which after being molded will become stiff or rigid to such an extent as to afford substantial support for the insole throughout the full width of the shank portion of the latter. rlhe reinforcing member herein shown is composed of ber impregnated with shellac, it having been found that shellac not only stiifens the fiber to the desired extent while permitting it to be softened to facilitate molding operations but also, when softened, serves as an adhesive capable of effecting a secure bond between the ber and tbe insole as a result of the molding operation. Other ingredients having characteristics similar to those of shellac may be employed for impregnating the fiber or other material employed in making the ller pieces or, if desired, unimpregnated fiber, leather or the like may be used, in which case the material is softened preparatory to molding it by immersion in wazer or other tempering fluid, after which the material is permitted to muli or temper until it is in suitable condition for use. ff no stiifening medium is employed for impregnating the ller piece material .an adhesive is employed for the purpose of uniting the filler pieces to the insoles.

In making a shoe bottom unit in accordance with the present invention, as herein exemplified. the following method is employed. A plurality of insoles are prepared by having their heel and shank portions coated on one side with shellac, as indicated at 2 in Fig. 1, means such as a brush 29 being used to apply the coating. After the coating has been applied the insoles are permitted to dry. A plurality of reinforcing members or ller pieces i9 are died out from berboard or similar material which has previously been impregnated with shellac for the purpose of stidening the material and the died-out filler pieces are prepared for assembly with the insoles by dipping the filler pieces in alcohol so as to soften the shellac and render the filler pieces readily moldable as well as capable of adhering to the insoles when pressed against the latter. After being dipped, the filler pieces are preferably stacked on edge in spaced relation in order that they may become thoroughly saturated with the solvent while the surplus solvent is permitted to drain away. Thistreatment of the filler pieces may be carried out with the aid of apparatus such as that shown in Fig. Zwhich comprises a tank 30 containing alcohol 32 and a rack 34 which is adapted to rest upon a shelf 36 carried by the tank, the shelf sloping toward the tank so that the surplus solvent may be conducted back into the tank. 'Ihe ller pieces may be dipped separately by hand and placed one at a time in the rack 34 or a plurality of filler pieces may be initially placed in the rack and the rack with the filler pieces therein dipped by a single operation. Also, if desired, the ller pieces may be cut from unimpregnated material and the cut pieces thereafter impregnated with shellac or other suitable stiffening ingredient which is capable of being subsequently softened and rendered adhesive upon the application of a solvent thereto.

After the above preparatory steps have been completed one of the prepared insoles is placed on a form, such as the last 40 shown in Fig. 5. The illustrated last 40 is provided with a metal heel plate 42 and is adapted to be supported upon a last pin in the customary manner. After having been positioned upon the last bottom, the insole i6 is secured to the last by means of tacks 44 driven through the forepart of the insole and into the wood of the last. Instead of the last 40 a metallic form may be employed, such as that shown at 46 in Fig. 4, in which case the insole may be secured in place upon the form by means of prongs 48 upon the form.

The metallic shank stiffener 20 is next positioned upon the shank portion of the insole and secured to the insole by means of a tack 50 driven through the rear portion of the shank stiffener and through the insole, the point of the tack being clenched against the surface of the insole by means of the metal heel plate, if a last is employed, or against the metallic surface of a form, if the latter is employed instead of a last.

One of the softened reinforcing members or filler pieces I8 is then positioned upon the heel and shank portions of the insole so as to cover the shank stifiener, except at the forward extremity of the latter, as shown in Fig. 5, and secured in place by means of a single tack 52 driven through the heel portion of the filler piece downwardly through the insole and through the usual tack hole 54 in the heel plate 42 and into the wood of the last, the tack thus serving to secure the heel portion of the insole as well as the filler piece to the last. AThe moisture in the filler piece will soften up the shellac coating on the insole, thus rendering a separate application of solvent to the insole unnecessary. The filler piece and the insole are thus adapted to be adhesively secured together upon the application-of pressure to the filler piece. In case certain stiffening ingredients other than shellac are employed for impregnating the filler piece, it may be found unnecessary to apply a coating of adhesive to the insole in order to secure satisfactory adhesion between the filler piece and the insole.

'I'he last or form, with the reinforced insole unit thereon, is then transferred to a press fitted to apply molding pressure to the shank portion only of the insole unit. If the insole unit is on a last the unit may be molded in a sole molding machine which, as indicated in Fig. 6 may comprise a. heel pin Gli and a toe rest 62 for supporting the iast, and a pressure-applying member in the form of a yieldable pad 64 carried by a vertically. recprocable pressure member 66, the pad 64 being shaped to apply pressuren substantially to the shank portion only of an insole upon the last. As shown, a layer of sheet material, such as wax paper, 68 is preferably inserted between the pad and the filler piece of the insole unit to prevent the filler piece from adhering to the pad.

The presser member 64 is operated to apply yielding pressure to the( ller piece, thereby causing the filler piece and the shank portion of the insole to be molded to the contour of the bottom of the last. As will appear upon reference to Figs. 6 and 7, the reinforced insole is molded to t exactly the contour of both the longitudinal and transverse curves of the last bottom. The molding pressure is maintained until the softened shellac has set, thus stiffening the filler piece and rmly securing it to the insole, thereby permanently retaining the shank portion of the insole in its molded form. A unitary shoe bottom member has thus been produced comprising an insole having a molded shank portion, a molded reinforcing member for the shank and heel portions of the insole adhesively secured tothe latter, and a metallic shank stiifener which is interposed and securely held in place between the insole and the reinforcing member. If the shoe bottom unit or reinforced insole was molded upon a form other than a last it is then removed from the form and transferred to a last upon the bottom of which it will fit perfectly because of its molded contour. If molded initially upon the last itself, it is preferably kept upon the last until after an edgebeveling operation has been performed thereon. This operation, as herein illustrated, is effected by presenting the insole unit, while on the last, to the action of a rotary cutter, such as that shown at 10 in Fig. 8, the cutter having a prole shaped to bevel the edge of the insole along the shank and heelportions as well as to bevel the opposite lateral edges of the reinforcing mem- Aber at such an angle as to blend smoothly with the profile of the corresponding portions of the last and thus to insure that, during subsequent lasting operations the upper will be drawn smoothly over the edges of the insole and the reinforcing member. Moreover, by beveling the edges of the insole unit, as above described, beveled faces are formed, the inner edges 0f which, being more or less sharply defined, will produce in the portions of the upper margins which overlie them corresponding more or less sharply defined shoulders or angles which advantageously serve to define the outer boundaries of roughened areas subsequently formed upon the overlasted upper margins to prepare them for the reception of cement for attaching, an outsole thereto. After being subjected to the abovementioned edge-beveling operation, the insole unit appears as shown in Fig. 9.

The insole unit is now ready for incorporation in a shoe and this is effected by assembling an upper on the last, pulling over and lasting the upper, and laying and attaching an outer sole 12. The pulling over of the upper and the lasting of the upper at the forepart is effected in the usual manner. In the shank portion of the shoe, however, the upper is lasted over the reinforcing member I8 and, as indicated in Fig. I0, is secured by fastenings, such as the staples 14, directly to the reinforcing member. As hereinbefore pointed out, the reinforcing member has been stiffened and toughened by the shellac or other ingredient with which it has been impregnated to such an extent that it affords a rm anchorage for the fastenings and serves to hold the latter more securely than would b the case if the fastenings were driven into the relatively week material constituting the insole I6.

Inasmuch as the insole unit has .been molded into iconformity with the contour of the last bottom an unyielding backing is provided for the stapledriving devices, thus insuringthat the staples will be uniformly driven into effective holding engagement with the insole unit. Consequently, there is no danger of the staples failing to hold in the shank portion of the shoe and thus releasing the tension of the upper and permitting it to pull away from the last before the outsole is attached. Moreover, there will be no yielding of the insole or shank stiifener while the outsole is being laid and consequently there will be no slackening of the tension of the upper from that cause such as might result in the formation of wrinkles in the upper. On the contrary, the upper will fit tightly over the last after the outsole has been laid and a smooth and shapely upper is insured in the finished shoe.

The outsole is laid with cement in the customary manner, but instead of engaging a metallic shank stiffener as usual it will engage the reinforcing member !8. Because of the molding of the insole and the reinforcing to the contour of the last bottom a solid bearing will be afforded for the outsole which is continuous throughout the full width of the shank portion of the shoe and arm bond will be established not only between the outsole and the lasted-over margins of the upper but also between the outsole and the reinforcing member it. Thus a secure and adequate adhesive attachment of the shank portion of the outsole is effected even in narrow shank shoes as well as perfect shaping of the shank of the outsole and adjacent portions of the upper to the contour of the last.

Having described my invention, what l claim as new and desire to secure by Letters Patent of the United States is:

l. A shoe bottom unit comprising an insole member having a longitudinally and transversely molded shank portion, and a reinforcing member longitudinally and transversely molded to conform to the molded shank portion of the insole member, said reinforcing member being impregnated with a stiffening or hardening medium and being adhesively secured by said medium to the insole, member.

2. A shoe bottom unit molded into conformity with the bottom contour of a last and comprising an insole, a reinforcing member impregnated with a stiifening medium andadhesively secured by said medium to the shank portion of the insole, and a shank stiffener interposed between the insole and said reinforcing member. A

3. That improvement in methods of Shoemaking which consists in softening a reinforcing member impregnated with an adhesive stiftening substance, assembling said softened reinforcing member with an insole member, and molding the assembled members to secure them together and to impart thereto a surface contour curved both longitudinally and transversely to correspond to the longitudinal and transverse curvature of the shank portion of the bottom of a last for a shoe in which the insole member is to be incorporated.

4. That improvement in methods of making reinforced insoles which consists in softening a reinforcing member impregnated with cementitious stiffening material to render it sticky and readily moldable, assembling an insole, a shank stiener, and said reinforcing member with the shank stiiener between the insole and the reinforcing member, and applying molding pressure accetta to the assembled parts to secure them together and to impart longitudinal and transverse curvature to the insole and the reinforcing member to correspond to that of the bottom of the shank portion of a last for a shoe in which the insole is to Abe incorporated.

5. 'lhat improvement in methods of Shoemaking which consists in placing an insole upon a last, laying upoxi the shank portion of the insole a shank stiffener having a longitudinal curvature corresponding to that of the last bottom, covering the shank stiifener and the shank and heel portions of the insole with a reinforcing member having a sticky surface, applying pressure to the reinforcing member to mold the shank portion of said member together with the shank portion of the insole to the contour of the shank portion of the last bottom and thereby rrnly securing together the insole, thereinforcing member and the shank stiiener to form a molded shoe bottom unit, and beveling the opposite lateral edges of the shank portion of said molded unit.

6. That improvement in methods of making reinforced insoles which consists in assembling upon a form an insole, a shank stiffener having a longitudinal curvature corresponding to that of the bottom of the form, and a moldable reinforcing member impregnated with cementitious stiffening material, softening said material to render said member sticky and readily moldable, and applying pressure to the assembled parts to mold the insole and the reinforcing member to the contour of the bottom of the form and to secure together the reinforcing member, the stienerand the insole.

7. That improvement in methods of making reinforced insoleswhich consists in applying an insole to a last, applying a solvent to a ller piece impregnated with cementitious material, placing upon the insole the ller piece together with a shank stirener having a longitudinal curvature corresponding to that of the last bottom, and applying pressure to the filler piece to mold the insole and ller piece to the shape of the shank g portion of the last bottom and to secure the filler piece, the shank stiifener and the insole together.

S. That improvement in methods of making reinforced insoles which consists in securing an insole to a last, positioning upon the outer face of the insole a shank stiifener having a longitudinal curvature corresponding to that of the last bottom, applying solvent to a filler piece iinpregnated with cementitious material, laying the ller piece upon the heel and shank portions of the insole, and applying yielding pressure to the ller piece to mold the filler piece and the insole to the contour of the shank portion of the last bottom and to secure together the ller piece, the shank piece and the insole.

9. That improvement in method of Shoemaking which consists in assembling an insole and a reinforcing member with adhesive between them, molding the assembled members and thereby securing them together to form a unit and imparting to the unit a surface contour curved both longitudinally and transversely to correspond to the longitudinal and transverse curvature of the shank portion of the bottom of a last for a shoe in which the unit is to be incorporated, and beveling the opposite lateral edges of the shank portions of the unit at the longitudinally concave side of the unit.

lil. That improvement in methods of Shoemaking which consists in placing an insole upon a last fili accenna the loottom of which is longitudinally concave and transversely convex in its shank portion, positioning upon the insole a shank stiffener curved to correspond to the longitudinal curvature of the shank'portion of the last bottom, placing upon the heel and shank portions of the insole a reinforcing member having a sticky surface, applying molding pressure to the shank portion of the insole and the reinforcing member thereley molding them to ht the last bottom and securing them adhesively together, beveling the opposite lateral edges of the shank portions of the insole and. the reinforcing member at the longitudinally concave side of the unit while the unit is on the last, lasting an upper over the margins of the unit, and laying an outsole and securing it to the overlasted portions o the upper.

ll'. lThat improvement in methods of making reinforced insole units as articles of manufacture which consists in cutting out an insole, cutting out a reinforcing piece for the "neel and shank portion of the insole, applying a coating of adhesive to at least one of said parts, assembling said parts with a shank stiifener interposed loetween them, molding the shank portions of the insole and the reinforcing piece to arch them both longitudinally and transversely while utilizing the molding pressure to secure them together, and thereafter heveling the opposite lateral edges of the shank portionsof the insole and the reinforcing piece.

l2. That improvement in methods of manufacturing shoes which consists in securing together an insole, a shank stiffener and a heel and shank reinforcing piece to make a reinforced insole unit, molding the shank portion of said unit to arch the same both longitudinally and transversely, beveling opposite lateral edges of the shank portions of the insole and the reinforcing piece, and thereafter placing the molded insole lili unit upon a last, lasting an upper and securing 2@ it to said unit, and completing the shoe.

KARL lElBURN. 

